Something like this might help to get updates. I know from owning a Toyota that they usually have updates on their websites that you can download after buying. Usually has to be put on the device through a correctly formatted usb stick.
https://apps.mitsubishi.navshop.com/en_us/support.html#mapupdatetool
https://www.mitsubishi-motors.com.au/owners/smartphone-link-display-audio.html